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TABLE 1 -CHECKLIST OF REQUIRED DATA
<br /> FOR NO FURTHER ACTION REQUESTS AT UNDERGROUND TANK SITES
<br /> Site Name and Location: CEMEX Tracy Facility, 30350 S. Tracy Blvd., Tracy, San Joaquin County(RB#390476)
<br /> Y 1. Distance to production wells for municipal, A 2014 sensitive receptor survey reported one water supply
<br /> domestic, agriculture, industry and other uses within well located 2,000'northwest of the Site. The well is not
<br /> 2000 feet of the site. threatened by the release.
<br /> Y 1 2. Site maps, to scale, of area impacted showing USTs Removals: 1/90, one 1,000 gallon diesel UST; 1/96, one
<br /> locations of any former and existing tank systems, 1,000 gallon gasoline, one 1,000 gallon and one 10,000 gallon
<br /> excavation contours and sample locations, boring diesel, and one 560 gallon waste oil USTs;5/99, one 6,500
<br /> and monitoring well elevation contours, gradients, gallon liquid asphalt UST. Site maps and figures showing tank
<br /> and nearby surface waters, buildings, streets, and locations, excavations, building and locations of residual
<br /> subsurface utilities; pollutants were provided in investigation reports.
<br /> Y 3. Figures depicting lithology(cross Site lithology consists of silt, sand,and gravel to 140', the total depth
<br /> section), treatments stem diagrams; investigated. No remediation was conducted.
<br /> N 4. Stockpiled soil remaining on-site or The quantity and fate of soil excavated during tank removal activities is not
<br /> off-site disposal(quantity); described in the available documents.
<br /> T5. Monitoring wells remaining on-site, Five remaining monitoring wells(MW-4 through MW-8) will be properly
<br /> destroyed prior to Site closure. .
<br /> 6. Tabidated results of all groundwater Depth to groundwater varied from 120'to 126'bgs during the investigation.
<br /> elevations and depths to water, Groundwater flow direction was northeast at a gradient of 0.0032 ft/ft.
<br /> 7. Tabulated results of all sampling All data adequately tabulated in various reports, including analyses for a waste oil
<br /> and analyses: tank. Soil contamination was delineated to non-detect in B-6 at 23'bgs in the tank
<br /> ❑
<br /> Y Detection limits for pit.
<br /> confirmation sampling
<br /> ❑Y Lead analyses
<br /> 8. Concentration contours of contaminants found and those remaining in TPHd was detected once in groundwater
<br /> soil and groundwater, and both on-site and off-site: monitoring wells;MW-6, 530 ug/L and MW-
<br /> 4, 440 ug/L in February 2013.
<br /> ❑Lateral and ElVertical extent of soil contamination
<br /> Lateral and Vertical extent of groundwater contamination
<br /> 9. Zone of influence calculated and assumptions used for subsurface An engineered treatment system was not
<br /> remediation system and the zone of capture attained for the soil and required by the regulatory agency.
<br /> groundwater remediation system;
<br /> 10.Reports/information❑ Unauthorized Release Form ❑Y QMRs (13) 7/03 to 9/13
<br /> 0 Well and boring logs 0 PAR FNJ FRP ❑Y Other Site Conceptual Model 10/14
<br /> Y 11.Best Available Technology(BAT)used or Leak was stopped by removing tanks.
<br /> an explanation for not using BAT,
<br /> UY 12. Reasons why background was/is not Groundwater is not impacted(9/13)by TPH. WQGs have been met.
<br /> finable using_BAT;
<br /> Y 13.Mass balance calculation of substance Residual TPHd mass in soil was estimated as 15,680 lbs. (2,375 gal.).
<br /> treated versus that remaining;
<br /> Y 14. Assumptions,parameters, calculations San Joaquin County determined that the Site meets the LTCP criteria
<br /> and model used in risk assessments, and fate for commercial use. Consultant states site does not represent a
<br /> and transport modeling; significant environmental or health risk under current use
<br /> (commercial).
<br /> Y 15. Rationale why conditions remaining at site Groundwater pollution was detected only once(2/13)during
<br /> will not adversely impact water quality, health, investigation. The regulatory agency determined that vapor intrusion
<br /> or other beneficial uses;and and dermal contact were not a significant environmental or health risk
<br /> under current use(commercial)
<br /> By: JLB Comments:From 1990 to 1999, multiple USTs were removed at the subject site. Soil at 15 below one of the
<br /> tanks was impacted by TPHd at 3,900 mg/kg. Based on groundwater impacts detected once in thirteen
<br /> Date: monitoring events, this case meets the LTCP. Regional Board staff concur with San Joaquin County's
<br /> 4/24/2015 Closure Recommendation.
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